diff --git a/python/requirements.txt b/python/requirements.txt
index d976fcd9f096..e04d5847ac42 100644
--- a/python/requirements.txt
+++ b/python/requirements.txt
@@ -53,7 +53,7 @@ scikit-image
 prometheus_client>=0.7.1
 requests
 pandas
-tensorboardX>=1.9
+tensorboardX<=2.6.0,>=1.9  # >=2.6.1 uses protobuf>=4, and conflicts with other packages.
 gymnasium==0.26.3
 grpcio<=1.50.0,>=1.42.0  # ray client
 aiohttp>=3.7
diff --git a/python/requirements/ml/requirements_train.txt b/python/requirements/ml/requirements_train.txt
index 4a6ac751c621..9ced832dc787 100644
--- a/python/requirements/ml/requirements_train.txt
+++ b/python/requirements/ml/requirements_train.txt
@@ -4,7 +4,7 @@
 
 mlflow==1.30.0; python_version <= '3.7'
 mlflow==2.4.1; python_version > '3.7'
-tensorboardX==2.4.1
+tensorboardX==2.6.0
 
 # Dependencies for Hugging Face examples & tests:
 # `python/ray/train/examples/transformers/transformers_example.py`
diff --git a/python/requirements_test.txt b/python/requirements_test.txt
index 2a17ed2e7eb9..0dcfb240d35a 100644
--- a/python/requirements_test.txt
+++ b/python/requirements_test.txt
@@ -96,7 +96,7 @@ importlib-metadata==4.10.0
 
 # Some packages have downstream dependencies that we have to specify here to resolve conflicts.
 # Feel free to add (or remove!) packages here liberally.
-tensorboardX==2.4.1
+tensorboardX==2.6.0
 starlette==0.17.1
 h11==0.12.0
 markdown-it-py==1.1.0